Eaton RTK 725B range - Modbus Master - Standard Communications

98
INM 725B Rev 21
13.4.17 Modbus Master – Standard Communications
Function Descriptions
This section describes the process of receiving messages from a RTK 725B master annunciator
Read Coil Status – Function 01 – Request
Register Address
This is used to address the “start” coil to be read from the slave device
Number of Registers
This represents the number of slave coils the RTK 725B wishes to read.
13.4.18 Read Coil Status – Function 01 – Response
Data
The data read from the salve device needs to be a valid value to operate the input.
If Channel set to Normally Open
Coil = 0 – Input Normal
Coil = 1 – Input Abnormal
If Channel set to Normally Closed
Coil = 0 – Input Abnormal
Coil = 1 – Input Normal
Typical Request Message Format Example
To read 100 coils from a slave with node address of 5 using the following message format
RTU
ADDRESS FUNCTION REGISTER ADDRESS No. of REGISTERS ERROR CHECK
05 01 00 00 00 64 3C 65
ASCII
: ADDRESS FUNCTION REGISTER
ADDRESS
No. of
Registers
ERROR
CHECK
CR LF
3A 30 35 30 31 30 30 30 30 30 30 36 34 39 36 0D 0A